You mean your springs are sitting on the bare aluminum head? Ik for sure mine have some kind of steel washer under the spring, I just had them off a few weeks ago to fix some stem seals. Maybe it's just a difference between years but obv neither of us have had problems.
I attached a picture of the shim on mine from when I found the bad valve seals. That thin shim is what came from OEM and I found an old convo with Mopar support and they actually told me to use that shim for these springs. So I assume it's just a difference between years, mines 2010 and you're both 2015+
Here's some info for the OP. Since 2013 uses the same seal as my 2010, as long as you have the 1mm shim and not the 2mm that some cars came with you can just reuse them.